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Show V ' " ' " s' " -" ! . -.-.', ' - " ' ' '.,"; - ..,,"" -.- . " yssijj ' . . ; '.? i, : f ; i ' ".-,-., '' 4 "i . ' A?,- ? . l if v' : The above Is a copy of what is probably the world's first photograph "printed" by bombardment of atomic rays. It shows the Westinghouse atom-smasher as pictured by a process developed devel-oped by Dr. Kuan-Han Sun, nuclear physicist at the company's research laboratories. A A A A ATOMIC PHOTOGRAPHY Nuclear Physicist 'Prints' First Photograph With Atomic Energy What is probably the world's first snapshot to be "printed" by atomic ray bombardment has been produced by a Westinghouse research re-search scientist. Dr. Kuan-Han Sun, Chinese-born nuclear physicist, recently displayed dis-played the unique photograph he made by bombarding film with neutrons neu-trons from the University of Pittsburgh cyclotron thus making the film radio-active. When held in contact with unexposed photographic paper, a replica of the picture on the film was produced on the paper. But the new process threatens no revolution in the photographic print business, Dr. Sun declared, adding that "it was tried purely as a research experiment with no commercial project in view. However, How-ever, it may well have applications in other fields, such as in the recording re-cording of secret papers for intelligence intel-ligence work or business transactions." transac-tions." Atoms Explode The scientist explained that the neutron bombardment rips into the atoms in the silver coating on the film, knocking out nuclear particles and making the atoms radioactive. These in turn hurl out high-speed electrons and gamma rays, and when a piece of sensitive photographic photo-graphic paper is held in contact with the film, a "carbon copy" of the picture is produced. Dr. Sun made the film by packing a sheet of film between blocks of paraffin wax. When neutrons from the cyclotron bombarded the encased en-cased film, they made it radioactive. radioac-tive. The blocks of wax were used to slow down the neutrons to desirable de-sirable speeds. The same radioactive effect ean be achieved, Dr. Sun said, by bombarding an ordinary glossy photograph, such as a snapshot. But it is easier to work with a positive sheet of film made from the original negative. In his experiment, the scientist first took a negative made of the Westinghouse atom-smasher atom-smasher and then converted It Into a positive film for the neutron neu-tron bombardment. Dr. Sun pointed out that although scientists have been recording radioactive atoms on film for many years in medical, metallurgical and other studies, this is the first time the process has been applied to pictorial pic-torial photography. The main difference, dif-ference, he explained, is that in the conventional process the "hot" atoms are introduced at the very beginning, whereas with the new technique the atoms involved are made radioactive "on location." Film Safe to Handle The process conceivably could be used to record secret documents for government or business transactions, trans-actions, Dr. Sun said. Here the information in-formation to be recorded would be written in invisible ink mixed with a substance that would become radioactive upon bombardment with neutrons. This could be either silver, sil-ver, or preferably some hard-to-detect compound which "captures" neutrons at a high rate and thus transforms itself into a radioactive medium. Once this was done, the hidden message would be revealed only upon contact with photographic photograph-ic film or paper. The scientist said that the intensity inten-sity of atomic radiation can be made low enough for the print or film to be handled with perfect safety. Dr. Sun said his work was only a small part of the stepped-up activity activ-ity in the field of atomic research underway in the United States. He believes there is no limit to the possible pos-sible uses atomic energy may be put in the future. Dr. Kuan-Han Sun, nuclear nu-clear physicist at the Westinghouse research laboratories, made the world's first atomic ray pictorial photograph. The new process may find application ap-plication in the recording of secret government or commercial documents. |